Protocols

There are times when we would like to describe the implementations (methods, properties, and other requirements) of a type without actually providing any implementation. For this, we can use protocols.Protocols define a blueprint of methods, properties, and other requirements for a class or a structure. A class or a structure can then provide an implementation that conforms to those requirements. The class or structure that provides the implementation is said to conform to the protocol.Protocols are very important to the Swift language. The entire Swift standard library is based on them, and we will be looking at protocols and how to use them in Chapter 8, Using Protocols and Protocol Extensions, and Chapter 9, Protocol Oriented Design.

Protocol syntax

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